This invention relates to electric storage batteries and more particularly to a termination strap for thin metal film battery cells.
A thin metal film battery cell includes plates made from very thin lead foil pasted with an active material on both surfaces. Plates with positive active material and plates with negative active material are separated by a separator strip and are spirally wound to form a roll. Unpasted edges of the positive plates extend in one direction while unpasted edges of the negative plates extend in an opposite direction from the roll. Terminations of lead or lead alloy are cast on or soldered to the ends of the spiral roll. U.S. Pat. No. 5,198,313 issued Mar. 30, 1993, for "Battery End Connector" describes one arrangement of cast-on end connectors for the two ends of a spiral roll.
The present invention provides a termination for a thin metal film roll in the form of a cap-like strap which uses less lead than the terminations of the prior art and which facilitates improved exposure of each of the spiral layers, or convolutions, to electrolyte. The strap also facilitates high voltage extrusion welding of the straps of adjacent cells.